261052631 has 4 divisors (see below), whose sum is σ = 298345872. Its totient is φ = 223759392.

The previous prime is 261052607. The next prime is 261052637. The reversal of 261052631 is 136250162.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 261052631 - 2¹⁸ = 260790487 is a prime.

It is a super-2 number, since 2×261052631² = 136296952304044322, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 261052631.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261052637) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18646610 + ... + 18646623.

It is an arithmetic number, because the mean of its divisors is an integer number (74586468).

Almost surely, 2^261052631 is an apocalyptic number.

261052631 is a deficient number, since it is larger than the sum of its proper divisors (37293241).

261052631 is an equidigital number, since it uses as much as digits as its factorization.

261052631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37293240.

The product of its (nonzero) digits is 2160, while the sum is 26.

The square root of 261052631 is about 16157.1232278522. The cubic root of 261052631 is about 639.1106062359.

The spelling of 261052631 in words is "two hundred sixty-one million, fifty-two thousand, six hundred thirty-one".